Area Forecast Discussion
Issued by NWS Bismarck, ND
Issued by NWS Bismarck, ND
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405 FXUS63 KBIS 020024 AFDBIS Area Forecast Discussion National Weather Service Bismarck ND 724 PM CDT Wed May 1 2024 .KEY MESSAGES... - Rain showers will develop across the west and central through this evening then spread eastward through tonight. An isolated thunderstorm is possible through this evening. - Showers and isolated thunderstorms could then be found Thursday and again Friday. Chances for showers and thunderstorms could then return Sunday evening into Monday. - Breezy to windy conditions are possible Friday, returning Sunday into next week. - Near to slightly below normal temperatures expected through Saturday, becoming near to above normal Sunday and Monday. && .UPDATE... Issued at 706 PM CDT Wed May 1 2024 Showers continue to lift northeast across portions of the forecast area. The most substantial are over the southwest/far south central and are forecast to become more widespread through the evening. There has been a decent amount of lightning over northwest South Dakota, but so far it has had a hard time making in north of the Border. Current forecast keeps thunder limited to the far southern tier counties this evening and this seems reasonable. For the early evening updated we blended a consensus of the latest short term guidance with our current pops. We also added some slight chance pops in the northwest early this evening to account for isolated showers moving into this area. && .DISCUSSION... Issued at 248 PM CDT Wed May 1 2024 A broad upper level low will slowly push into the area tonight. As it does so, scattered becoming numerous showers look to develop across the CWA. A general risk of thunderstorms continues to be found across western and central portions. Confidence in thunderstorms is fairly low through tonight given the limited instability. There are some hints of some increased cape moving in from SD in the southwest this evening. These areas may be the more likely areas to see thunderstorms tonight, although over confidence is low and severe weather is not expected. A more broad area of showers is then expected to develop ahead of the upper low across central and eastern portions overnight tonight. Low temperatures tonight look to be in the lower 30s to mid 40s, and most areas of precipitation should be warm enough for all rain. Upper low then stalls across the state on Thursday. This will linger widespread rain across the east, and develop scattered to numerous showers across the central and perhaps some western portions. Instability is increased for Thursday, although still on the lower ends. Shear is also low given the broad and stacked upper low pattern. Thus a few thunderstorms are possible for Thursday afternoon and evening, although severe weather is not expected at this time. High temperatures on Thursday will be near to perhaps slightly below normal, and generally in the 50s. The upper low then becomes slightly more progressive for Friday. This could linger chances for showers and perhaps a few isolated thunderstorms, especially in the north. A push of colder air will also lower temperatures into the upper 40s to upper 50s Friday, with 30s possible Friday morning. Perhaps these cooler temperatures could allow for some snow to mix in Friday morning, with little to no impacts expected. This cold push could also bring some increased westerly winds on Friday. QPF totals in the next 48 hours, most areas will have a 60 to 80% chance of seeing at least 0.10." There is a 10 to 60% chance of 0.50" with the higher chances coming in the central and east. There is even a 10 to 30% chance of at least an inch of QPF by the end of precipitation on Friday, mainly in central portions. This weekend then looks to start off mainly dry. Saturday is more of a transition day as the upper low pulls out of the area. Temperatures could remain near to slightly below normal, although winds are diminished and the chances for precipitation are generally less than 10%. Sunday sees warming temperatures as an upper level ridge brings southerly flow. A strong gradient at the surface could also bring some breezy winds on Sunday. Temperatures could warm into the 70s for most areas on Sunday. Clusters then indicate the next period of active weather could start Sunday night and continue into next week. A broad trough looks to push into the region, with perhaps a cut off low forming after it does so. There are some timing differences in the clusters as well as differences how/if this upper low forms. Overall though chances for rain look to return end of the weekend into next week. Temperatures may start off mild, then look to return near normal. Of note for Sunday and Monday are the CSU-MLP chances for severe weather starting to return across the west on Sunday and across much of the CWA on Monday. Deterministic models are somewhat limited on instability during this time, yet do have ample amounts of shear. Something to monitor going forward. The other item to monitor with this pattern is the potential for breezy to windy conditions almost each day to start next week. This will depend how the surface low wraps up. ECMWF EFI values are elevated each day to start next week and will also be worth monitoring. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 706 PM CDT Wed May 1 2024 scattered to numerous showers will spread northeast across southwest and central ND tonight through Thursday morning. Isolated to scattered showers and isolated thunderstorms possible across western and central ND Thursday afternoon. Showers are currently moving into southwest and central ND to begin the 00Z TAF period and continue to lift northeast through the night. As we get into the late evening and overnight hours expect widespread rain showers with MVFR to IFR ceilings and Visibilities spreading northeast across the area. KBIS and KJMS look to be the most likely to be impacted with both IFR ceilings and MVFR to possibly IFR visibilities as showers are forecast to track from south central into eastern ND. At this time it appears KDIK and KMOT will be on the western fringes of the areas of widespread showers, but will likely see periods of MVFR ceilings and visibilities and occasional rain showers this evening and into the overnight. KXWA may remain VFR through the period. Thursday afternoon it`s possible we could see a period of diurnally driven showers and isolated thunderstorms, but at this time it`s too far out to mention at the end of the TAF period. Winds across the areas tonight will be generally southerly and around 12 knots or less. On Thursday winds will shift westerly from west to east across the forecast area. Winds may become breezy in the southwest Thursday afternoon, including KDIK with winds west 15-25 knots in the afternoon. && .BIS WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE... DISCUSSION...Anglin AVIATION...TWH